随着转基因产品商业化种植面积不断增加、国际贸易日趋频繁,对转基因生物安全管理提出了更高的要求.转基因产品检测技术作为安全评价的关键环节,逐渐引起了各国政府的关注.目前,针对转基因产品的快速检测方法层出不穷,但这些检测方法对于设备、试剂和专业的实验人员均有较高的要求.因此,为了有效支撑转基因相关产业的发展和管理,亟需建立一种高灵敏度、高特异性及高效的转基因检测技术.基因组编辑技术是近年来迅速发展的一类遗传修饰技术,其代表技术——CRISPR/Cas技术,更是极大地推动了生物技术的发展.CRISPR/Cas技术除了被应用于基因编辑领域,也逐渐被应用于核酸分子检测领域.基于此,以转基因产品检测技术为立足点,从CRISPR/Cas的检测原理、检测效果等技术层面分析了CRISPR/Cas检测技术发展的必然性,并对其在转基因产品检测上的应用前景进行展望,旨在为我国转基因产品快速检测和有效监管工作提供资料,对于保障我国转基因产品贸易的顺利进行具有重要意义.

目的 建立符合我国国情的食品欺诈数据库,补充国际上已建立的经济利益驱动型掺假(economically motivated adulteration,EMA)数据库空白.方法 搜集2001～2019年发生的食品欺诈行为,初步建立具有中国国情的食品欺诈数据库.对数据库中信息完备的454条欺诈数据进行分析.结果 媒体报道数据占食品欺诈信息总数的71.6％;食用农产品、酒类、乳制品、肉制品等11类产品是欺诈事件发生较多的食品类别;产品欺诈(72.2％)高居食品欺诈类型的首位;2001～2019年食品欺诈事件数量呈现出先上升后降低,再上升再降低的"M"状趋势;目前食品欺诈检测技术主要以理化分析技术为主,针对的食品类别还有限;食品欺诈信息以中国为主(89.0％),涉及到世界各个地区.结论 食品欺诈是广泛存在的全球性问题,本研究建立的食品欺诈数据库为预防食品安全风险起到了重要的技术支撑作用.

对内蒙古农业大学校园内表现花器绿变症状的菊花样品进行采集和DNA提取,应用植原体16SrRNA基因和rp基因的引物进行巢式PCR扩增,从感病样品中分别扩增得到了长度均约为1.2 kb的片段.序列一致性分析表明,菊花绿变植原体16S rRNA基因与翠菊黄化植原体匈牙利风信子株系(GenBank登录号MN080271)、印度玉米株系(KY565571)、印度繁缕株系(KC623537)和印度马铃薯株系(KC312703)的核酸一致性最高,为99.9％,rp基因序列与翠菊黄化植原体立陶宛洋葱株系(GU228514)的核酸一致性最高,为99.8％.基于16S rRNA基因和rp基因构建系统进化树时发现,菊花绿变植原体均与16SrI-B亚组成员聚为一起.16S rRNA基因相似性系数分析表明,菊花绿变植原体与洋葱黄化植原体(AP006628)的相似性系数最高为1.00,洋葱黄化植原体(AP006628)在分类上属于16SrI-B亚组.因此,我们可以确定该菊花绿变植原体属于16SrI-B亚组.这是我国首次报道菊花绿变病的发生.

The probes of 10 plant viruses and control were designed and immobilized on chips.The total RNA was extracted by Trizol method from plants.Primers were designed according to the sequences of cp gene or rep gene of the plant viruses.The corresponding fragments were amplified by RT-PCR and the PCR products were labeled by Cy3-dCTP.The labeled PCR products were hybridized with the probes and the signals were scanned by scanner and analyzed by GenePix Pro 4.0 software.Specific signals were identified from virus-infected plants.The detection sensitivities of gene chip were 10-100 times higher than RT-PCR.The results indicate that gene chip can be used for detection of plant viruses fast and accurately.

s A pair of specific primers was designed based on the conserved region of the coat protein gene of Tobacco streak virus.Total RNA was extracted from infected soybean leaf and was reverse transcribed to cDNA. The cDNA was subjected to PCR using the forward and reverse primers. PCR product was cloned into pGEM T-Easy vector and transformed the E. coli DH-5α. Target fragment about 430bp was found when the inserted plasmid was digested with Not I. The inserted fragment was sequenced. It consisted of 404 nucleotides.

A one-step RT-PCR kit was developed for the detection of tobacco ringspot virus(TRSV) with the special primers,which were designed based on the published sequence of TRSV and application procedure.The sequence analysis showed 97.8 % nucleotide acid identity between the positive product of the kits and the published sequence,and the result showed that the reagents system and the application procedure were right.After stored at-20 ℃ for two months at last,at 4 ℃ for one week or at room temperature for two days,the kits still could be used for the detection,which sensitivity was 100 times more than that of DAS-ELISA and the result of quality control was same.

A virus was isolated from naturally infected Cucurbita moschata in Beijing. It was identified as Zucchini yellow mosaic virus by biological, serological and molecular biological tests. In order to analyzing the characterization of the 3′ terminal sequences of the genome, the 3′ terminal sequences were amplified cy RT-PCR form total RNA of infected leaves and cloned into pMD18-T vector. The sequences were 1269bp and contained the coat protein (CP) gene, which consisted of 837 nucleotides encoding 279 amino acids. The analysis was carried out in 30 isolates on their 760 bp segments (containing the 3′ terminal 56bp of NIb gene and 704bp of CP gene), the incising site of Nib protein and CP, the mutation of the sequence which was related to aphid transmissibility, the source of hosts and terrains. The result showed that the gene types of ZYMV were not obviously related to the five factors.

<正>李属坏死环斑病毒(Prunus necrotic ringspot virus,PNRSV)属雀麦花叶病毒科(Bromoviridae) 等轴不稳环斑病毒属(Ilarvirus),是我国二类检疫 性有害生物。PNRSV主要危害李属和蔷薇属植 物。如,樱桃、桃、李、月季等。春季感染PNRSV 的樱桃早期幼叶会出现深棕色坏死斑和线纹,叶片 展开期坏死斑脱落造成穿孔症状。受PNRSV危 害后,果树树势减弱,产量降低,甚至死树。我国学 者调查陕西、辽宁和山东等省的果树病害时发现并 报道了该病毒。

Bean pod mottle virus is an economically important virus that infect soybean.A pair of specific primers was designed based on the conserved region of the coat protein gene of bean pod mottle virus.Total RNA was extracted from infected soybean leaves and was reverse transcribed to cDNA.The cDNA was subjected to PCR using the forward and reverse primers.PCR products of 650 bp were generated from all isolates tested.The RT-PCR method could be used to detect BPMV-infected soybean leaves with satisfied results that were confirmed by DAS-ELISA assay.We recommended ELISA assay to detect BPMV-infected soybean seed rather than RT-PCR.

随着我国加入WTO和植物及其产品的国际间贸易的发展,为更好地适应新的世界贸易体制,遵守SPS协定及其透明度的原则,同时有效地发挥检疫的技术性贸易壁垒作用,迫切需要利用计算机技术建立有害生物风险分析模式.

随着加入WTO和经济的全球化,我国植物检疫工作面临新的形势,特别是进境产品的增加,导致疫情更加复杂,检疫把关难度增大.为此,需要采取一些新的举措,如建立预警机制、开展有害生物风险分析等,来解决检疫工作中遇到的新问题.与此同时,针对性检疫仍将在现行的植物检疫体制中起着一定的作用.长期以来,作为一项基本检疫策略,其核心就是把一些国内还没有发生或者分布不广的、特别危险的、可以人为传播的有害生物作为"检疫对象",由国家正式公布,国家植物检疫机构根据相关法令,对凡有可能传带这些检疫对象的物品,实行检验检疫,一旦发现有规定的检疫对象,即可根据有关规定采取相应的检疫处理措施[1].

利用血清学技术开发的酶联诊断试剂盒,由于快速灵敏,操作简便,可进行大量样品的检测,比较好地满足了生产上需要,具有广阔的应用前景.